An imaging apparatus is known including an image sensor in which imaging pixels and focus detection pixels are disposed in a mixed state on the same substrate, capturing a subject image formed by an imaging lens on the image sensor, and detecting a focusing state of the image (for example, Patent Document 1). Any of color filters in R (red), G (green) or B (blue) is equipped on each imaging pixel so as to be a pattern in Bayer array type. On the other hand, a white filter is equipped on the focus detection pixel so that a focus detection can be done for a subject in any color. Accordingly, a pixel value in accordance with a normal color filter cannot be acquired at a location of the focus detection pixel in an image data captured by the above-stated imaging apparatus. A method interpolating a pixel value for imaging at the location of the focus detection pixel is proposed in the Patent Document 1 and so on by using a pixel value of an imaging pixel in a vicinity of the focus detection pixel. Patent Document 1: Japanese Unexamined Patent Application Publication No. 2007-282109